1. Field of the Invention
The present invention relates to rechargeable battery packs having a flexible printed circuit board that defines a current path for transferring current to a protection circuit module from unit cells of the rechargeable battery.
2. Description of the Related Art
Rechargeable batteries may be repeatedly charged and discharged, unlike primary batteries. Low-capacity rechargeable batteries may be used for portable compact electronic apparatuses, for example, mobile phones, notebook computers, and/or camcorders. High-capacity rechargeable batteries may be used as a power source for, for example, driving a motor of an electric bike, a scooter, an electric vehicle, a fork lift and the like.
Rechargeable batteries can be used as a unit cell or a plurality of unit cells electrically connected depending on a type of employed apparatus. Rechargeable battery packs can comprise unit cells, a protection circuit module (PCM) for protecting the unit cells, a flexible printed circuit board (FPCB) for connecting the unit cells to the protection circuit module, and a case for accommodating these components.
The plurality of unit cells can be electrically connected in series or in parallel to make tablet-type rechargeable battery packs. For instance, three flexible printed circuit boards can be used in the rechargeable battery packs which connect six unit cells in parallel. A problem encountered in arrangement of the unit cells in the case is the difficulty in securing arrangement spaces of the flexible printed circuit boards connecting a negative electrode lead tab and a positive electrode lead tab to the protection circuit module. For this reason, there is a difficulty in securing a current path in the flexible printed circuit board.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention, and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.